Since I develop on one platform and my production servers will be on
another, I use virtualization a lot. You can use Microsoft Virtual PC,
or VMWare’s products. I am using Microsoft’s Virtual Server, which has
a free download, and a 180 day evaluation license. Despite the name, it
runs on Windows XP too.
With enough memory, I can run a QA system, or a full production
simulation - multiple web server, multiple app servers, database
servers. Just don’t run any performance tests!
The problem with trying to run a QA system on the same box as a dev
configuration is that, with all these GEM_HOME and other configurations,
is this really the same as the QA or production machine is running? The
further away you get from what you want, the less useful the process